1. Technical Field
The present invention relates to poly(acrylic acid) polymer blends. More particularly, The present invention relates to blends of poly(acrylic acid) and glycerol with fluid-absorbent and elasticity properties that are prepared by a solution casting process. These polymer blends are especially suitable for applications such as but not limited to biomedical applications and personal disposable hygiene products.
2. Description of the Related Art
The “background” description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description which may not otherwise qualify as prior art at the time of filing, are neither expressly or impliedly admitted as prior art against the present invention.
Poly(acrylic acid) (PAA), which is also known as carbomer, is one of the most significant water soluble polymers and forms the base of a class of materials termed ‘super absorbent polymers’ because of its ability to absorb water many times of its original volume and also its capability to retain water under pressure. As a result of these unique features, PAA is widely used in applications such as controlled release devices, membranes, disposable diapers, ion exchange resins, tissue engineering, toothpastes and so on J. Jose, F. Shehzad, and M. A. Al-Harthi, “Preparation method and physical, mechanical, thermal characterization of poly(vinyl alcohol)/poly(acrylic acid) blends,” Polym. Bull., July 2014—incorporated herein by reference in its entirety]. The swelling performance of PAA can be controlled by crosslinking reaction and copolymerization or via preparing composites by incorporating suitable nanofillers through solution polymerization [J. Lin, J. Wu, Z. Yang, and M. Pu, “Synthesis and Properties of Poly(acrylic acid)/Mica Superabsorbent Nanocomposite,” Macromol. Rapid Commun., vol. 22, no. 6, pp. 422-424, March 2001; A. Li, A. Wang, and J. Chen, “Studies on poly(acrylic acid)/attapulgite superabsorbent composite. I. Synthesis and characterization,” J. Appl. Polym. Sci., vol. 92, no. 3, pp. 1596-1603, May 2004; Z.-Q. Zhu, H.-X. Sun, X.-J. Qin, L. Jiang, C.-J. Pei, L. Wang, Y.-Q. Zeng, S.-H. Wen, P.-Q. La, A. Li, and W.-Q. Deng, “Preparation of poly(acrylic acid)-graphite oxide superabsorbent nanocomposites,” J. Mater. Chem., vol. 22, no. 11, p. 4811, February 2012—each incorporated herein in its entirety]. Blends of PAA with poly(vinyl alcohol) (PVA) and with poly (2-hydroxyethyl vinyl ether) (PHEVE) prepared by solution mixing and casting process show high degree of miscibility with an increase in storage modulus with temperature [W. Herrera-Kao and M. Aguilar-Vega, “Storage modulus changes with temperature in poly(vinyl alcohol), PVA,/poly(acrylic acid), PAA, blends,” Polym. Bull., vol. 42, no. 4, pp. 449-456, May 1999; V. V. Khutoryanskiy, M. G. Cascone, L. Lazzeri, N. Barbani, Z. S. Nurkeeva, G. a. Mun, A. B. Bitekenova, and A. B. Dzhusupbekova, “Hydrophilic Films Based on Blends of Poly(acrylic acid) and Poly(2-hydroxyethyl vinyl ether): Thermal, Mechanical, and Morphological Characterization,” Macromol. Biosci., vol. 3, no. 2, pp. 117-122, February 2003—each incorporated herein by reference in its entirety]. Also, the addition of PAA to PVA caused a considerable reduction in crystallinity and the prepared blends showed sensitivity to pH changes during swelling test [N. A. Peppas and D. Tennenhouse, “Semicrystalline poly (vinyl alcohol) films and their blends with poly (acrylic acid) and poly (ethylene glycol) for drug delivery applications,” J. Drug Deliv. Sci. Technol., vol. 14, no. 4, pp. 291-297, 2004—incorporated herein by reference in its entirety]. The subsequent thermal treatment leads to the formation of cross-linking between PAA with methyl cellulose polymer and the prepared material has ability to swell in water and ethanol [V. V Khutoryanskiy, M. G. Cascone, L. Lazzeri, Z. S. Nurkeeva, G. A. Mun, and R. A. Mangazbaeva, “Phase behaviour of methylcellulose-poly(acrylic acid) blends and preparation of related hydrophilic films,” Polym. Int., vol. 52, no. 1, pp. 62-67, January 2003—incorporated herein by reference in its entirety]. Recently, it was found that the developed blends of PAA and poly(ethylene glycol) are potential material for thermal energy storage applications at their miscibility conditions [C. Alkan, E. Gunther, S. Hiebler, and M. Himpel, “Complexing blends of polyacrylic acid-polyethylene glycol and poly(ethylene-co-acrylic acid)-polyethylene glycol as shape stabilized phase change materials,” Energy Conyers. Manag., vol. 64, pp. 364-370, December 2012—incorporated herein by reference in its entirety].